In Washington, D.C., all firearms must be registered with the police, by the terms of the Firearms Control Regulations Act of 1975.
The same law also prohibited the possession of handguns, even in private citizens' own homes, unless they were registered before 1976. However, the handgun ban was struck down by the U.S. Supreme Court in the 2008 case District of Columbia v. Heller. The Supreme Court ruled that the Second Amendment acknowledges and guarantees the right of the individual to possess and carry firearms, and therefore D.C.'s ban on handguns was unconstitutional.
A lawsuit was filed on August 6, 2009 to compel the district to issue permits to carry weapons.